Arrangement and method for collecting oil

ABSTRACT

The invention relates to an arrangement and a method for collecting oil from water in open water and/or winter conditions, whereby a vessel&#39;s hull and oil collecting equipment are utilized as an oil collector. According to the invention, the oil collecting equipment is attached to the vessel&#39;s hull and it is equipped with an auxiliary device, which comprises at least two auxiliary means which are interconnected so that they are movable with respect to each other. The auxiliary means can be utilized in various ways in different conditions.

This is a national stage application filed under 35 USC 371 based onInternational Application No. PCT/FI2002/000904 tiled Nov. 14, 2002, andclaims priority under 35 USC 119 of Finnish Patent Application No.20012276 filed Nov. 21, 2001.

The invention relates to an arrangement for collecting oil from water inopen water and/or winter conditions.

Solutions are already known, by means of which oil is collectedmechanically from the surface of the sea. Mechanical oil collecting isalso the oil spill prevention method recommended by the Baltic MarineEnvironment Protection Commission in the Baltic Sea area. As an oilcollector can function e.g. a collector floating independently, whichhas been described in patent publication FI 73029. In this publication,oil is collected from water and ice inside a device through holestherein.

A separate oil collecting means to be attached to the vessel andcollecting oil with the help of bristles to a water flow channelarranged in a vessel, is disclosed in patent publication FI 85528.

The prior art has considerable disadvantages. Probably the most seriousdisadvantage is, that they are difficult to adapt to oil collecting inhard wind and rought seas. In addition, oil collecting with the knownsolutions is slow. Therefore wind velocity of 10–15 m/s and significantwave height of 1.5 m are used as limiting values of the environmentalconditions. When these limiting values are exceeded, the collecting isinterrupted or its efficiency is significantly lowered and the risk forthe oil collecting equipment to be damaged will increase. Furthermore,booms are generally used for collecting oil and for leading it tocollecting device and due to their susceptibility to damages, thecollecting speed is lmited to 1.5 knots at maximum. A speed higher thanthis also makes the oil escape underneath the boom.

Further from publication DE 2843952 A1 is known a solution, in which thevessel's hull is used as an oil collector. The hull of the vessel ismore durable and higher than the fabric or rubber structure boom used inprevious structures. The strength of the structure enables raising ofthe collecting speed and makes the oil collecting possible in weatherconditions and ice conditions considerably worse than before. The heightof the broad side of the vessel to be used as an oil collector alsohinders the oil from escaping underneath the vessel's broad side orunderneath a device connected thereto, making possible also the use of ahigher collecting speed. The disclosed known solution is, however, quitetheoretical and no attention has been paid to oil collecting indifferent conditions like in open water as well as in winter conditions,in which case there are blocks of ice in the water.

It's an aim of the invention to eliminate the disadvantages related tothe prior art and to provide a new solution suitable for a moreefficient oil collecting and for various kinds of weather conditions.

The invention is based on the idea, that when the vessel is moving to adirection, which can be freely chosen at a certain angle with respect tothe direction of the vessel's bow, the vessel's broad side acts for itspart as an oil collector. Further, an oil collecting equipment isattached to the vessel's hull, including an oil collecting means forseparating oil from water and an auxiliary device for leading the oil tobe separated to the oil collecting means. The oil collecting means knownper se can comprise e.g. a brush cleaner. For intensifying the oilcollecting, the auxiliary device comprises at least two auxiliary means,which are interconnected so that they are movable with respect to eachother. Consequently, it can be chosen which auxiliary means are used ineach case and in which way, whereby, when the vessel is advantageouslysteered at an appropriate propagation angle, oil can be collectedoptimally from an area as wide as possible in different conditions.

During oil collecting, the auxiliary device may be located mainlyoutside the vessel's hull. Alternatively, under certain conditions, itmay be partly or entirely inside the vessel's hull and/or on the deck ofthe vessel. The auxiliary device may be fixed to the vessel's hull andforms part of it or it may be installed separately. Oil collecting canalso be intensified so that the auxiliary device is located at the rearend of the vessel's hull, in which case the widest possible collectingwidth is obtained.

In practice, the auxiliary means included in the auxiliary device may befunctionally connected so that they form a uniform wall, hatch or thelike. This kind of solution is well adapted to open water conditions.

The auxiliary means included in the auxiliary device advantageouslycomprise two different-sized walls, hatches or the like. In this case,the smaller one of the said auxiliary means is preferably arrangedinside the bigger one so that it can be turned separately inside thevessel's hull for winter use. The auxiliary means can be advantageouslyarranged to turn in relation to the same stub shaft.

Furthermore, for winter use, the oil collecting equipment can beadvantageously provided with a device for separating oil from ice priorto feeding it to the oil collection means. In practice, the said oilseparating device may comprise an inclined plane, the inclined bottom ofwhich is arranged below the said smaller auxiliary means.

The turning angle of the auxiliary means may be adjusted in someconvenient manner e.g. mechanically, hydraulically, pneumatically,electrically or electromechanically and the vessel itself is steeredadvantageously at a certain propagation angle with respect to itsdirection of travel. The steering process may, when required, beautomated by taking account of the ship's direction of travel, force ofthe wind, height of the wave etc. criteria, so that oil collecting canbe carried out in an optimal way according to the calculationsperformed.

Advantageously, the vessel's broad side functioning as an oil collectoris as straight as possible, possibly even a little bit concave, in form.E.g. icebreakers and passenger ships can be used as the oil collectingvessel. The so-called inclined icebreaker is considered to be the mostsuitable and it being especially designed to be steered effectivelysideways even at large propagation angles with respect to its directionof travel. For this purpose the vessel is advantageously asymmetricalwith respect to its longitudinal direction and further equipped withsteering propulsion devices placed both on the rear side and bow side,with the help of which the vessel can be steered, if necessary, bothforwards and backwards.

A second aspect of the invention relates to the method for applying thepresent arrangement. According to the invention, the vessel's hull isutilized for collecting oil and breaking ice and is equipped with an oilcollecting equipment including, in addition to an oil collecting meansknown per se, also at least two auxiliary means, with the help of whichthe oil is led to the oil collecting means. The auxiliary means can beindependently adjusted, if necessary. In this case a functionallyuniform wall or hatch can be formed to the vessel's broad side, which isturned to a certain angle outwards with respect to the vessel's side,thus providing a more efficient oil collecting in open water conditions.On the other hand in winter conditions, when there may be ice in thewater, advantageously only one, advantageously the smaller-sized, of theauxiliary means is used. If this auxiliary means is additionally turnedinside the hull, the oil or the oily water may be collected to thevessel without exposing the hatch or the corresponding auxiliary meansin question to stress caused by the ice.

For intensifying the oil collecting, the vessel is preferably steered sothat its centre line forms, depending on the propagation speed, the mostpreferable propagation angle with respect to the vessel's direction oftravel from the viewpoint of oil collecting. From the view point of thecollecting width it is, of course, advantageous that the auxiliary meansfor collecting the oil are located possibly far at the rear of thevessel at the broad side thereof.

In open water, the said propagation angle (E;F) is chosen preferablywithin the range 20°–70°, whereby the angle of the auxiliary means (10a) with respect to the vessel's broad side (3) is at least 20°–70° andat the most 40–140°. Correspondingly, in winter conditions thepropagation angle (E;F) is chosen preferably within the range 0°–30°,whereby one auxiliary means (10 a) is not opened and the other auxiliarymeans (10 b) is opened entirely.

In case the said two auxiliary means comprise two different-sizedinterconnected auxiliary means, in winter conditions the smaller-sizedis advantageously turned inside the hull.

The separation of oil form ice can take place e.g. with a known devicefastened outside the board like e.g. with the device according to patentFI 106969, which presses the ice under water and separates the oil fromthe ice and leads the oily water to a collector outside or inside thehull, in which the oil is separated from the water by using a techniqueknown per se.

Considerable advantages can be obtained with the invention. Thus withthe present invention, the collecting speed can be considerably raised,which enables collecting of oil from a larger area per time unit. It ispossible to perform the oil collecting in open water weather conditionsfar worse than before, but it can also be done in winter ice conditions.

The invention is described below, by way of example, with reference tothe accompanying drawings, in which:

FIG. 1 shows side view of a vessel suitable for oil collecting accordingto the invention,

FIG. 2 shows a section along line G—G of the vessel of FIG. 1,

FIG. 3 shows the vessel's motion at a certain propagation angle withrespect to its direction of motion,

FIG. 4 shows a schematic illustration of the vessel from above, theauxiliary means turned open,

FIG. 5 shows sideways an auxiliary device added to the vessel,

FIG. 6 shows a device according to FIG. 5 viewed from above,

FIG. 7 shows sideways an alternative auxiliary device added to thevessel,

FIG. 8 shows the auxiliary device of FIG. 7 viewed from above and indifferent kinds of operating positions.

An oil collecting arrangement comprises a vessel 1, which is equippedwith an oil collecting equipment 4. The equipment includes an oilcollecting means known per se, e.g. a collection belt functioning withbristles, which separates the oil from the surface of the water andleads it to oil collecting tanks located inside the vessel (not shown inmore detail in the Figures). In FIG. 1, the vessel's hull as a whole isindicated with number 2 and the water surface with the arrows G. Thepropulsion devices steering the vessel are marked with the reference 9.With these the vessel can be steered to different directions of travel.

In FIG. 2, there is shown separately the ship's advantageously quitestraight broad side 3, which is utilized for obtaining the best possibleoil collecting result. In addition to the equipment 4, there is markedwith the arrow A in the figure the vessel's normal direction of traveland with the arrow B the vessel's direction of travel in exceptionalcases, e.g. when breaking the ice. In order to be able to collect oil asefficiently as possible, the vessel is steered in the direction C i.e.there is a deviation of an angle E with regard to the normal steeringdirection. Correspondingly, if the conditions so require, the vessel issteered in the direction D i.e. there is a deviation of an angle F withregard to the prevailing travelling direction. In this connection, theangles E and F are called the propagation angles of the vessel.

The FIG. 3 shows the vessel moving diagonally sideways at thepropagation angle E in direction C, whereby the purpose is to reach anoil collecting area L as wide as possible for collecting oil optimallyby utilizing the vessel's broad side 3 and by taking account of, as faras possible, also e.g. the force of the wind, the height of the waveetc. The oil collecting area can be broadened if the oil collectingequipment 4 is located at the rear part of the vessel.

The FIG. 4 shows an oil collecting equipment 4, which comprises anauxiliary device 7 and an oil collecting means 6, which is locatedeither inside the vessel or on deck 5 thereof. The auxiliary device 7 isturnably supported to the vessel's broad side 3 at a fixing point 8. Theauxiliary device 7 may, according to the need, alternatively besupported also from the other end thereof e.g. in a solution, which isused when the vessel is advancing diagonally backwards i.e. to thedirection marked with D in FIG. 2. In addition, it is possible to use anauxiliary device 7, which is made of two different parts and each partis fixed to opposite sides of an opening in the hull.

The FIG. 5 shows sideways the auxiliary means connected to the vessel,which includes a bigger hatch or the like 10 a and a smaller hatch orthe like 10 b. The vessel is further equipped with a device 11 forseparating oil from ice prior to leading it to the oil collecting means.In FIG. 6, the solution is viewed from above. The device 11 can be atits simplest an inclined plane, the lower surface 11 a of which preventsice from entering through the hatches 10 a and 10 b. In case of FIG. 6,typically in winter conditions, the bigger hatch 10 a is entirely closedand the smaller hatch 10 b is turned inside the vessel's hull.

The FIG. 7 shows a modified version of the invention, which includesalso a two-part auxiliary means 10 a, 10 b and which can also be usedfor collecting oil both in summer and in winter. In summertime, bothparts 10 a and 10 b are advantageously opened simultaneously. In winter,with advantage only one of the auxiliary means, the smaller one 10 b, isused for oil collecting.

The FIG. 8 shows the solution of FIG. 7 viewed from above, in differentoperating positions of the auxiliary means. In other words, forcollecting oil according to the conditions, both auxiliary means 10 aand 10 b may be open, and especially in winter conditions, the biggerauxiliary means 10 a may be entirely closed and the smaller auxiliarymeans 10 b may be turned inside the vessel's hull 2.

Within the scope of invention, also solutions different from theabove-described ones are feasible. There may be several differentauxiliary means i.e. hatches or the like, which may be in different waysturnably supported to the vessel's hull and/or to each other. Above, theinvention is applied mainly to an icebreaker or a tugboat, but nothingprevents applying the same kind of solution to ordinary vessels e.g.merchant ships or passenger ships. Therefore, separate components, thatcan even be detachable either form the vessel's hull or attached anddetached e.g. from aboard of the vessel, can be used as an auxiliarydevice. The dimensions of the auxiliary device may, of course, vary agreat deal. Also, the material of the auxiliary device may be anymaterial appropriate for the purpose like e.g. different kinds ofmetals, plastics or combinations thereof.

Consequently, the invention is not limited to the embodiments shown, butseveral modifications of the invention are feasible within the scope ofthe attached claims.

1. A vessel comprising: a hull having a broad side and formed with anopening in the broad side of the hull, an oil separating means forreceiving oil and water and separating the oil from the water, and anauxiliary device for cooperating with the hull to collect oil and leadthe oil and water to the oil separating means, wherein the auxiliarydevice comprises at least two wall members that are interconnected sothat they are movable with respect to each other, the auxiliary device,when in a closed position, forms part of tho hull, and the hull has arear end and a forward end and the auxiliary device is attached to thehull at the rear end thereof.
 2. A vessel according to claim 1, whereinthe auxiliary device is attached to the hull at a broad side thereof. 3.A vessel according to claim 1, wherein the oil separating means islocated at least partly inside the hull of the vessel.
 4. A vesselaccording to claim 1, wherein the oil separating means is located on adeck of the vessel.
 5. A vessel according to claim 1, wherein the oilseparating means is attached to the hull in a manner allowing detachmentof the oil separating means from the hull.
 6. A vessel according toclaim 1, wherein the auxiliary device is attached to the hull in amanner allowing turning movement of the auxiliary device relative to thehull.
 7. A vessel comprising: a hull having a broad side and formed withan opening in the broad side of the hull, an oil separating means forreceiving oil and water and separating the oil from the water, and anauxiliary device for cooperating with the hull to collect oil and leadthe oil and water to the oil separating means, wherein the auxiliarydevice comprises a larger wall member formed with an opening and asmaller wall member that is connected to the larger wall member in amanner such that in a first position the smaller wail member blocks theopening in the larger wall member and in a second position the smallerwall member is turned inward of the larger wall member relative to thehull.
 8. A vessel according to claim 7, wherein the hull is formed withan opening in a broad side of the hull and the larger wall member isturnable relative to the hull between a first position in which itblocks the opening in the broad side of the hull and a second positionin which it is deployed outboard of the hull.
 9. A vessel according toclaim 8, wherein the auxiliary device has a first operational conditionin which the larger wall member is in its first position and the smallerwall member is in its first position and the auxiliary device blocks theopening in the broad side of the hull and the smaller wall member blocksthe opening in the larger wall member, a second operational condition inwhich the larger wall member is in its first position and the smallerwall member is in its second position, and a third operational conditionin which the larger wall member is in its second position and thesmaller wall member is in its first position.
 10. A vessel according toclaim 7, comprising a device for separating oil from ice present in thewater prior to feeding the oil to the oil separating means, the oilseparating device having a bottom wall that is inclined to horizontaland is located below the smaller wall member.
 11. A vessel comprising: ahull having a broad side and formed with an opening in the broad side ofthe hull, an oil separating means for receiving oil and water andseparating the oil from the water, and an auxiliary device forcooperating with the hull to collect oil and lead the oil and water tothe oil separating means, wherein the auxiliary device is turnablerelative to the hull according to the vessel's direction of travel, theauxiliary device comprises at least two wall members that areinterconnected so that they are movable with respect to each other, theauxiliary device, when in a closed position, forms part of the hull, thehull has first and second opposite longitudinal broad sides that areasymmetrical with respect to each other, the auxiliary device isprovided at the first broad side, and the first broad side issubstantially straight over a substantial portion of its length.
 12. Avessel comprising: a hull formed with an opening in a broad side of thehull, an oil separating means for receiving oil and water and separatingthe oil from the water, the oil, separating means being located withinthe hull and being accessible from outside the hull through saidopening, and an auxiliary device that is movable with respect to thehull between a first position in which the auxiliary device blocks saidopening and a second position in which the auxiliary device is deployedoutboard of the vessel for cooperating with the hull in collecting oiland leading the oil and water through said opening to the oil separatingmeans, wherein the auxiliary device comprises at least two wall membersthat are interconnected so that they are movable with respect to eachother.
 13. A vessel according to claim 12, wherein the wall memberscomprise a larger wall member that is turnable relative to the hullbetween a first position in which it blocks the opening in the broadside of the hull and a second position in which it is deployed outboardof the hull, and a smaller wall member that is attached to the largerwall member and is turnable relative to the larger wall member between afirst position in which it blocks an opening in the larger wall memberand a second position in which it is turned inward of the larger wallmember relative to the hull.